Recently, a friend and her sister visited a retirement community in our neighborhood. They chatted up several residents, including the sweet, 90-year-old widower who’d lost his beloved wife some months before. When they turned to leave, he asked the sister for her phone number. Since she is 50 and married, they laughed it off. Not long after, they heard that their elderly Don Juan had found himself a girlfriend in a nearby senior living community and was visiting her regularly.

The anecdote is cute, but it also points to a larger reality. We are never too old to enjoy sex—that’s the entire premise of this website—but somewhere on the road to the golden years, single seniors have thrown youthful caution to the winds when it comes to safe sex. The result is that sexually transmitted infections (STIs), such as Chlamydia and syphilis, are spreading more quickly among people over 55 than among any other age group except 20-24 year olds, according to a 2010 report from the Center for Disease Control and Prevention (CDC).

Even more alarming—one in four people with HIV/AIDS is over 50. In the Sunbelt, where large communities of seniors live, the rates of increase are off the charts: In two counties in Arizona cases of syphilis and Chlamydia among those over 55 rose 87 percent between 2005 and 2009; in central Florida, the increase was 71 percent, according to this article in Psychology Today. News reports use words like “epidemic” and “skyrocketing” to describe these increases. Medicare has begun offering free testing for STIs, but most (95 percent) of seniors remain unscreened.

What the heck is going on here? What happened to all those lectures in responsibility and self-control we subjected our kids to? What seems to be happening is that we are, luckily, more long-lived and healthier than our forebears. We are also newly empowered with drugs to maintain erections for men and to make sex more comfortable and enjoyable for women. All the years of hard work, career-building, and childrearing are in the rearview mirror. Many of us find ourselves alone and treading tentatively back into this brave, new world of sex and dating. Add to this the sometimes freewheeling life in retirement communities (some of which are the size of small cities), which create hotbeds (no pun intended) of people of similar age and background—kind of like a college dorm.

Trouble is, unlike kids in a dorm, seniors don’t have to worry about pregnancy and aren’t nearly as well-informed about the risks of unprotected sex. Condom use for those over 60 is the lowest for any age group (6 percent vs. 40 percent for college-age males). And condoms, in case you’ve forgotten, provide the only dependable protection against STIs, and even they aren’t effective against every sexually transmitted bug.

Also unlike their much younger counterparts, older folks have a less robust immune system, so the chances of catching and spreading infections are higher. Plus, many STIs are asymptomatic, so the person doesn’t know he or she is infected—and that the STI is degrading the immune system even further. Finally, doctors rarely think to ask Grandpa about his sex life in the normal course of an exam, even if he has classic symptoms of an STI.

All this adds up to a lively Petri dish of bugs circulating around the singles scene. Yet, prevention is so easy, and the cost of ignorance or of ignoring common-sense precautions is high. So, ladies, even if the prospective partner is someone you’ve known all your life, don’t assume you’re familiar with the intimate details of his sexual forays. Others have walked this path before—and are paying the price. Jane Fowler, 71, and founder of HIV Wisdom for Older Women, was infected with HIV by just such a friend when she was 55 and now advocates for more information and support for older women with AIDS. I’d suggest that if you’re dating, stick a couple condoms in your purse right with the lipstick. And get yourself tested if you’ve ever had unprotected sex. And read this series of posts about STIs on MiddlesexMD. The rule of thumb these days—better safe than sorry.